improved comments

following @terrelln suggestions
This commit is contained in:
Yann Collet
2018-03-06 18:15:26 -08:00
parent 06ca9c7d7c
commit db147ea620
+6 -2
View File
@@ -1279,6 +1279,10 @@ static size_t ZSTD_decompressSequencesLong(ZSTD_DCtx* dctx,
return ZSTD_decompressSequencesLong_default(dctx, dst, maxDstSize, seqStart, seqSize, nbSeq, isLongOffset); return ZSTD_decompressSequencesLong_default(dctx, dst, maxDstSize, seqStart, seqSize, nbSeq, isLongOffset);
} }
/* ZSTD_getLongOffsetsShare() :
* condition : offTable must be valid
* @return : "share" of long offsets (arbitrarily defined as > (1<<23))
* compared to maximum possible of (1<<OffFSELog) */
static unsigned static unsigned
ZSTD_getLongOffsetsShare(const ZSTD_seqSymbol* offTable) ZSTD_getLongOffsetsShare(const ZSTD_seqSymbol* offTable)
{ {
@@ -1331,10 +1335,10 @@ static size_t ZSTD_decompressBlock_internal(ZSTD_DCtx* dctx,
ip += seqHSize; ip += seqHSize;
srcSize -= seqHSize; srcSize -= seqHSize;
if ( (dctx->fParams.windowSize > (1<<24) || !frame) if ( (!frame || dctx->fParams.windowSize > (1<<24))
&& (nbSeq>0) ) { /* could probably use a larger nbSeq limit */ && (nbSeq>0) ) { /* could probably use a larger nbSeq limit */
U32 const shareLongOffsets = ZSTD_getLongOffsetsShare(dctx->OFTptr); U32 const shareLongOffsets = ZSTD_getLongOffsetsShare(dctx->OFTptr);
U32 const minShare = MEM_64bits() ? 7 : 20; U32 const minShare = MEM_64bits() ? 7 : 20; /* heuristic values, correspond to 2.73% and 7.81% */
if (shareLongOffsets >= minShare) if (shareLongOffsets >= minShare)
return ZSTD_decompressSequencesLong(dctx, dst, dstCapacity, ip, srcSize, nbSeq, isLongOffset); return ZSTD_decompressSequencesLong(dctx, dst, dstCapacity, ip, srcSize, nbSeq, isLongOffset);
} }